public class ConcreteDecoratorSerial extends Decorator {

    public ConcreteDecoratorSerial(Component component,String content) {
        this.setComponent(component);
        this.setContent(content);
    }

    @Override
    public String operation(){
        // 上层操作的返回值
        String superContent = super.operation();
        return superContent + "<serial>" + this.getContent() + "</serial>\n";
    }

}
